Drag bush



Feb. 6, 1923. 1,443,967

D. T. SHARPLES.

DRAG BusH. FILED MAY 14, 1921.

or wEs'r DAVID TOWNSEND SHARPLES,

THE SHARPLES SEPARATOR COMPAN CORPORATION OF PENNSYLVANIA.

Appilcation filed May 14 To all whom it may concern Be it known that 1, DAVID TOWNSEND SHARPLEs, a citizen of the United States, residing at WVest Chester, in the county of Chester, State of Pennsylvania, have invented certain new and useful Improvements in Drag Bushes, of whlch the follow; mg 1s a descrlption, reference being had to the accompanying drawing andto the figures of reference marked thereon.

This invention relates to steadying bearings for preventing wabbling or other irregular motion of the shaft or spindles rotating at high speeds and in particular, to-a steady? mg bearing or drag bush for centr fugal bowl separators or the like. g

The manner in which these drag bushes function in connection with centrifugal separator bowls is clearly disclosed in I the United States patent to McCormick No. 706,- 088, issued August 5, 1902, and since the invention re'lates only to the improved construction of the bush itself, the recitation of" the invention will in the main be confined to the description of the improved bush. In this prior patent, as in present constructions, the drag bush surrounds the bottom end of the separator bowl from which itis slightly spaced and functions to confine the lower end of the revolving bowl within nary row' 'limits without using the bush asan actual bearing. 'So long as the bowl orits bottom boss is revolving truly and in place, there is no frictional contact between-the bowl or boss and thesurrounding bush, although the surface of the bowl boss and the inner surface of the drag bush are very close to one another, approximately onethirty second of an inchor less. If,however, the bowl is swayed from its true. position by any force, the bowl bottom comesinto contact with the bush and to an extent is guided by it. Thebush, however, is mount-' ed in a position so that it may shifthori- Zontally under slight friction, so that when the bowl swings against it, the bush moves slightly to one slde, thus making a drag on the lateral motion of the bowl but not con fining it in the sense of-a bearing. These bushes are generally made of wood, such as hard maple, because such a surface pre-' sents little friction when the bowl occasion--- allytouches it, and second, because it is light enough to prevent hammer action. Wooden CHESTER, r N svLvANIA, ASSIGNOR 'I'O Y, or wEsrcn sr PENNSYLVANIA, 'A

DRAG BUSH.

, 1921. Serial No. 469,519.

.bushes, however, have stant source of trouble,

- always been a con-f owmgto their shrinking and swelling when dry or wet. At-

tempts'have been made'toprevent this obthese bushes water-proof oil or otherwise and then enclosing them in tight fitting i of the wood the wood absorbed the moisture it but not being able to V to the metal band, it the hole smaller.

dried outa little it the metal shell and more in size.

move outwardly, owing the hole contracted still It has also-been proposedto make these bushes of Babbitt metaL'b'ut they did not provide theideal frictional surfaces present inthe wooden bushes jectionable expansion byxfir'st' rendering] by soaking themjin metal casings, but the tendencywas toigr'ow smaller, for when expanded,

closed inwardly, making So also, when the bush" shrunk, became loose in The present invention overcomes all of these difficulties by providing'a woodenor fiber bush which maintains its inner circumferential dimensions although the bush is free to expand and contract under ordinary working conditions, f

A further object ofthis invention resides in constructing so v a wooden or fiber drag bUSlI'WlllCll permits a circular expansion and if contraction of the bush'material but not a radial expansion inner circumference ofthe bush is maintained.

sen another object of this invention re Y prov ding a wooden or fiber drag sides in orcontraction'so that the e '85 bush which is free to expandand contract circularly but'not radially, due" toone or more slots or severances entirely through the annular wall of'the bush and due to the re-f strlctiveinfluence of a metal orother ring which is non-'expansible under working con ditions,':which metal ring permits thebush material to expand circularly about the ring it from radial expansion or contraction.

Still another feature of this invention re,- sides in the simple manner in which the bled.

These and other objects will in part be obvious and will in part be hereinafter more fully disclosedg g Referring I ore particularly to the accompanying drawings i i F'gure 1 is a side elevation partly in secbush is constructed and maintained assern-.

by reason of the severances while restraining tion of my improved drag bush shown in proper position surrounding the boss on the lower end of a centrifugal bowl separator;

Fig. 2 is an enlarged sectional View of the drag bush; V

Fig. 3 is a plan view thereof, and

Fig. 4 is a modified form of bush.

In Figure 1 of the drawings, the improved drag bush is disclosed in connection with an improved type of centrifugal bowl separator in which the outer casing 1 is mounted on a suitable supporting bracket and encloses the separator bowl 2 which issuspended freely in said casing and rotated from above by suitable mechanism.

Thelower end of the cylindrical bowl 2 is closed by-a' removable plate or, plug 5 which is threaded into the lower end of the bowl, and suitable means is provided for forming. a tight joint connection between this plate and the bowl proper- Said plug or plate 5 is provided with an inlet opening 6. The casing 1 is formed with an'opening 7 in which is placed a ferrule 8, the upper end of which is turned inwardly to form a flange 9. The central opening through the flange 9 is slightly larger than the project ing end 10 ofthe plate 5. Located within the ferrule 8 is a'drag bush 11 which is slightly spaced from the projecting end 10,

the separation being approximately pone thirty-second of'an inch. The specific construction of this drag bush willibe described later. The spring 12 bears against the bush 11 at its upper end and at its lower end against a housing 13, provided with an ex tension 14 fitting the cylindrical lug 15 carried by the receptacle 16. This receptacle 16 is adapted to engage the lower end of the casing 1 and is suitably secured thereto;

The drag bush 11 is forced by means of the spring against the flange 9. The diameter of thisdrag bush is less than the inner diameter of the housing 13. It will be evident from the above construction that when the lower end of the bowl wabbles or deviates from its true axis of rotation, the boss 10 which is normally spaced from the inner circumference of the-drag bush, will come into'frictional engagement with the inner circumference of this drag bush, which en gagement will, cause the lateral displaceinent of the bush on its seat 9 against which or the cut segments are provided with concentric grooves 19 and :20 placed in the upper and lower faces of the ring. A ring 21 of metal or material which does not expand or contract when subjected to moisture, is arranged in each of these grooves, 19 and 20. This ring 21 has such a predetermined circumference that the segments 18 will be assembled in spaced relation, the inner circumference of the bush when thus assembled being of a predetermined dimension so that the inner wall 22 of the bush will be spaced a desired distance from the outer wall of the end 10 on the lower end of the bowl, about, one thirty-second of an inch.

In Figure t, another type of bush is shown, wherein the ring 11' is provided with a single severance or slot 18 entlrely" through the annular wall. This ring is provided as before with a desired number of metallic'rings 21 to maintain the adjacent ends of the severed ring in spaced relation and the .inner circumference of predetermined dimension. I

It will be evident from the above constructo expansion or contraction, the metallic ring will effectively prevent any change in dimensions of the inner circumference for the reason-that the expansion will take place by reason of the wood in the segments creeping circularly around the metal ring tion that when the; drag bush is subjected j so as to take up the hiatus between the se-gments. In other words, the material of the ring will not expand or contract radially,

but is more or less free to expand or con-f tract circularly. Having thus described the invention, what I claim as new and desire to secure by Letters-Patent, is

1. A drag bush for a separator bowl or the like comprising a Wooden or fiber ring having a predetermined inner circumference, said ring having at least one severance entirely through its annular wall, and means preventing the radial expansion of said ring while permitting its circular 7 expansion due to said severance.

2'. A drag bush for a. separator bowl or f the like comprising a Wooden or fiber ring having a predetermined inner circumfen.

once, said ring being composed of a plurality 1 i of normally spaced segments, and means, for

maintaining such inner ciirumferencewhile.

permitting the expansion and contraction of said segments.

3. A drag bush for a separator bowl or the like comprising a wooden or fiber ring composed of one or more segments, means for normally holding said segments assembled in spaced relation, said means preventing the radial expansion and contracf tion of such segments while permitting their circular expansion and contraction. e. A drag bush for a separator bowl or the like comprising a wooden or fiber ring having a predetermined inner circumfer ence, provided with a concentric groove therein and formed with at least one severance through its annular Wall, a ring having a fixed circumference disposed in said groove for preventing the radial expansion or contraction of said ring While permitting its circular expansion or contraction.

5. A drag bush for a separator bowl or the like comprising a plurality of Wooden or fiber segments assembled in normally spaced relation to form a ring having a predetermined inner circumference, said segments being grooved to form aregistering concentric groove on the face of the as sembled ring and a ring having a fixed circumference disposed in said'groove for pre venting the radial expansion of said segments While permitting their circular expansion. I

6. A drag bush for a'sep'arator bowl or the" like comprising a Wooden or fiber ring provided with a concentric groove in each face and formed'of a plurality of segments, a metal ring of predetermined circumference ineach grooveto assemble said segments in normally-spaced relation, said ring preventing the radial expansion or contraction of said segments While permitting their circular expansion.

In testimony whereof, I afiix my signature.

DAVID TOWNSEND Sl-lARPLESi 

